The clinical value of CT attenuation values diagnosis of hydronephrosis with infection

Objective To investigate the diagnostic and clinical significance of computerized tomography (CT) attenuation values (hounsfield unit, HU) in hydronephrosis with infection. Methods One hundred and eighty-five cases of upper urinary tract calculi with hydronephrosis from June 2014 to June 2016 were retrospectively analyzed. There were 82 males and 103 females with a mean age of (52.3±13.1)years old, ranging 18-80 years old. 58 cases suffered hydronephrosis without infection, 55 cases suffered acute pyelonephritis and 72 cases suffered pyonephrosis. The CT attenuation values of the renal pelvis urine in three groups were measured. Results The CT attenuation value of hydronephrosis without infection group was (5.61±3.67)HU, 95%CI(4.64-6.57)HU . In acute pyelonephritis group, CT attenuation value was (8.35±5.63)HU, 95%CI(6.83-9.87)HU. In pyonephrosis group, the CT attenuation value was (13.92±6.21)HU, 95%CI (12.46-5.38)HU. The CT attenuation value of pyelonephritis compared with that of hydronephrosis without infection was significant different.(P<0.01). The CT attenuation value of the patients with pyonephrosis was significantly higher than that of patients without infection and with pyelonephritis (P<0.01). Conclusions The CT attenuation value of renal pelvis urine can predict intrarenal infection. Furthermore, The measurement of CT attenuation value has some clinical significance in preoperative evaluation of hydronephrosis with infection. Key words: CT attenuation value; Pyonephrosis; Pyelonephritis; Hydronephrosis